with \(J=400\)  K, \(J^{\prime }=1\)  mK, we find \(T_N^{2D}=54\)  K, while \(T_N^{1D}=3\)  mK from eq.(REF ). In both cases, the model fails to describe
(TMTTF)\(_2\) SbF\(_6\) . Our results should help the extension of the 1D and 2D
models connecting \(T_N\)  and the exchange couplings [1]}, [2]}
to the cases of intermediate dimensionality, \(J_a>J_b\gg J_c\) .
